My first priority is always the max rear axle weight rating and the max tire weight rating. The amount a dodge, and probably any brand truck, can trailer/pull is a lot more than sticker. The trade off will be how it affects your transmission and brakes.
I had an 2005 SRW cummins and the GRAW was 6100#, tires rated at 6300#. With my 5th hooked up I was at 5750# rear weight. But my GCWR was over the sticker by 800#. The truck handled the trailer well enough and stopped it fine. Just took a little longer to start or stop..
Mine was a factory truck, no suspension work or anything else. It did sit down on the overload bump stops, but I didn't feel it differently.
Just my .2cents.
Thanks,